Coating mat

ABSTRACT

A COATING MAT FORMED FROM A SHEET OF RESILIENT MATERIAL WHICH IS ADAPTED TO BE WRAPPED AROUND THE OUTER SURFACE OF A ROTARY CYLINDER. THE COATING MAT INCLUDES A MAGNETIC BACKING OR A MAGNETIC MEMBER FOR SECURING THE MAT TO THE CYLINDER. THE MAGNETIC MEMBER IS SECURED TO AT LEAST THE LEADING EDGE OF SAID MAT AND IS ADAPTED TO BE POSITIONED IN A SLOT PROVIDED IN THE ROTARY CYLINDER. THE MAGNETIC   MEMBER INCLUDING A STRIP OF MAGNETIC MATERIAL FOR MAGNETICALLY HOLDING THE LEADING EDGE OF THE SHEET OF RESILIENT MATERIAL IN TIGHT ENGAGEMENT WITH THE CYLINDER. REGISTRATION OF THE COATING MAT IN THE PROPER POSITION OF THE SURFACE OF THE ROTARY CYLINDER IS PROVIDED BY THE SLOT FOR THE MAGNETIC MEMBER.

A. M. BRAY COATING MAT Filed June 28, 1971 Feb. 6, 1973 72 INVENTOR ll/ll BY ,l/vwm 4/. 09 7d %W4 ,lfmewzy United States Patent Office 3,714,692 COATING MAT Andrew M. Bray, Little Suamico, Wis., assignor to Magna-Graphics Corp., Dayton, Ohio Filed June 28, 1971, Ser. No. 157,182 Int. Cl. B21b 31/08 US. Cl. 29-129 13 Claims ABSTRACT OF THE DISCLOSURE A coating mat formed from a sheet of resilient material which is adapted to be wrapped around the outer surface of a rotary cylinder. The coating mat includes a magnetic backing or a magnetic member for securing the mat to the cylinder. The magnetic member is secured to at least the leading edge of said mat and is adapted to be positioned in a slot provided in the rotary cylinder. The magnetic member including a strip of magnetic material for magnetically holding the leading edge of the sheet of resilient material in tight engagement with the cylinder. Registration of the coating mat in the proper position on the surface of the rotary cylinder is provided by the slot for the magnetic member.

BACKGROUND OF THE INVENTION In coating and die cutting operations, a resilient mat is provided on one of the rotary cylinders of the coating or cutting device to hold the material being treated in a predetermined position while a coating or die cutting operation is being performed on the material. The resilient material used on these rolls is subject to extensive wear and requires periodic replacement. Generally, considerable time and expense is required in changing the coating roll since it was often easier to remove the entire cylinder and replace it with a new cylinder than it was to remove the mat from the cylinder. In some instances, removable segments are provided in the areas where the greatest wear occurs resulting in an uneven surface between the old and new mat.

SUMMARY OF THE PRESENT INVENTION The coating mat of the present invention can be quickly and easily mounted on and removed from the outer periphery of a rotary cylinder. The coating mat is quickly and easily secured to the cylinder by either a magnetic member or magnetic backing provided on the coating mat. When the magnetic member is used, the rotary cylinder is provided with an axially extending slot in its outer peripheral surface. The leading edge and in some instances the trailing edge of the resilient mat is provided with the magnetic member which is simply inserted into the slot and retained therein by magnetic force. If a more positive hold-down is required, a magnetic member can be attached to both the leading and trailing edges of the resilient mat and inserted into the slot in a magnetically interlocked position. Positive registration of the resilient mat on the cylinder is also provided by a pair of adjustable members located at each end of the slot.

When a magnetic backing is used, the entire coating mat is secured to the outer periphery of the cylinder. This is achieved by providing a sheet of flexible magnetic material to the entire back of the coating mat.

Other objects and advantages will be apparent from the following description when read in connection with the accompanying drawings.

THE DRAWINGS FIG. 1 is a perspective view of a rotary cylinder showing one form of the resilient mat of this invention secured to the outer surface of the cylinder;

3,714,692 Patented Feb. 6, 1973 FIG. 2 is a view of a portion of the end of the cylinder showing a single magnetic member on the leading edge of the mat and a magnetic backing on the mat;

FIG. 3 is a fragmentary view of an alternate embodiment of the present invention showing a magnetic member mounted on both the leading and trailing edges of the resilient mat;

FIG. 4 is an enlarged view taken on line 4-4 of FIG. 2 showing a cross sectional elevation of a portion of the magnetic member;

FIG. 5 is a fragmentary view taken on line 5-5 of FIG. 1 showing the registration screws;

FIG. 6 is a fragmentary view of a portion of a rotary cylinder showing another embodiment of the invention wherein the magnetic members are magnetically interlocked in the slot in the cylinder;

FIG. 7 is a fragmentary view showing a resilient mat having a metallic sheet and a magnetic backing; and

FIG. 8 is a fragmentary view of another embodiment of the coating mat having a magnetic backing.

DESCRIPTION OF THE INVENTION A pressure roller as used herein refers to a resilient type roller that is used as a backing for a coating or die cutting operation. Referring to FIGS. 1 and 2 of the drawings, a pressure roller 10 is shown which generally includes a rotary cylinder 12 and a resilient mat 14. The rotary cylinder 12 is of the type generally used for a coating or die cutting operation having shafts 16 extending from each end. The cylinder 12 is generally made of steel. In any of these types of cylinders, the mat 14 is used to provide a resilient back-up for the particular operation which is being performed in the machine. The cylinder 12 can be provided with an axially extending slot 15 across the full length of the cylinder 12 for retaining and registering the mat on the cylinder as described below.

In accordance with the invention, the resilient mat 14 is formed from a unitary or single sheet of resilient material 13 which can be either plastic, rubber, synthetic or the like. In one form of the invention as seen in FIG. 2, a thin metallic backing plate 18 is provided on the back of the resilient material 13 to increase the rigidity of the mat, if desired. The mat 14 has a length substantially equal to the circumference of the rotary cylinder 12 so that the leading end 20 and trailing end 22 form a butt joint 25 axially across the length of the cylinder 12.

In the embodiment shown in FIGS. 1 and 2, means in the form of a magnetic member 30 is secured to the leading edge 20 of the plate 118 to hold the mat 14 on the cylinder. The magnetic member 30 is inserted into the slot 15 in the cylinder and is retained therein by the magnetic force of the member 30.. In this regard, the member 30 includes a channel member 3-2 and a permanent magnetic strip 34 secured to the inside of the channel member 32. The channel member 32 is formed of either a magnetic flux insulating material or magnetizable material and is secured directly to the resilient material v13 or to the backing plate 18 as shown in FIG. 2. The channel member 32 should have a width less than the width of the slot 15 in the rotary cylinder 12 so that it can be inserted easily into the slot 15 and pulled tightly against the wall 17 of the slot 15 to initially register the mat on the cylinder. The channel member 32 has a length less than the width of the mat 14 and is closed at each end by means of a flap 35 formed as an integral part of the resilient material 13.

The magnetic strip 34 is formed of a permanent magnetic material like Plastiform (rubber bonded barium ferrite material) made by 3M Company. The strip 34 is adhesively secured or bonded in the channel member 32 in a position to engage the cylinder 12. In this embodiment only the leading edge 20* is secured in the slot 15.

It should be understood that the magnetic material can be provided with any magnetic pole arrangement.

Means can also be provided for magnetically securing the entire mat 14 to the outer surface of the cylinder 12. Such means is in the form of a sheet 36 of flexible permanent magnetic material such as Plastiform as described above. The permanent magnetic sheet 36 is adhesively secured to the metallic backing plate 18, as in FIG. 2. The magnetic sheet 36 will hold the resilient mat 14 in tight engagement with the cylinder 12-.

Accurate registration of the resilient mat 14 is achieved by means of set screws 40 provided in the angularly offset threaded openings 42 at each end of the cylinder 12. In this regard and referring to FIG. 5, the set screw 40 is shown extending through the angular offset opening 42 for movement into engagement with the magnetic assembly 30. The slot 15 in the cylinder 12 is slightly wider than the magnetic assembly 30 to allow for a limited amount of movement of the member 30 after assembly.

The following procedure should be followed in registering the mat 14 on the cylinder 12. The magnetic assembly 30 is inserted into the slot 15 and pulled against the side Wall 17 of the slot as the mat is wrapped around the outer periphery of the cylinder. If the indicia provided on the side of them at 14 is not aligned with the corresponding indicia on the side of the cylinder 12, the screws 40 are rotated to move the magnetic assembly 30 away from the wall 17 of the slot 15. The mat 14 will resist or restrain the movement of the channel member 32, as the screws 40 are turned into engagement with the ends of the channel member 32 to register the mat 14, the channel members will tend to bow in the slot 15 due to the resistance of mat 14. Once the mat has been aligned, the mat 14 should be removed from the cylinder 12 and the channel member 32 again placed in the slot in abutting engagement with the ends of the screws 40'. The mat is again wrapped around the cylinder 12 and will then be aligned on the cylinder. Although the amount of motion required to register the mat may appear small, it is often critical in certain operations.

In the embodiment shown in FIG. 3, the leading end 44 and the trailing end 46 of a resilient mat 48 are provided with means for magnetically holding the mat 4 8 on the cylinder. In this regard, the leading end 44 and the trailing end 46 are formed to abut in the slot 15. A first magnetic member 30 is embedded in the lead end 44 and a second magnetic member 30 is embeded in the trailing end 46. The magnetic members 30' are positioned for magnetic engagement with the cylinder 12. Although the members 30 are shown embedded in them at 48, they can also be secured to a backing if used as described above.

In the embodiment shown in FIG. 6, a resilient mat 60 having a metal or magnetic backing 65 is shown having means in the leading end 62 and the trailing end 64- for magnetically abutting the ends 62 and 64 in the slot 15. Such means is in the form of first and second magnetic assemblies 3G welded or bonded to the backing 65. In this embodiment, the trailing end is initially placed in the slot 15 and the mat 60 wrapped about the cylinder 12. The leading end '62 is then pushed against the trailing end 64 with the magnetic assemblies 30 in abutting engagement.

If the coating mat is used on a pressure roller for a die cutting operation, it is not necessary to have a slot in the cylinder 12. A mat 70 as shown in FIG. 7 or a mat 72 as shown in FIG. 8 can then be used. The mat 70 in FIG. 7 includes a sheet of resilient material 74 having an intermediate sheet of metallic material 76 secured to the back of the material 74. A sheet of magnetic material 78 is secured to the metallic sheet 76. The mat 70 should have a length sufiicient for the ends 80 and 82 to abut when mounted on the cylinder. In FIG. 8, the metallic sheet 76 has been eliminated and the magnetic material 78 is secured directly to the resilient material 74.

What is claimed is:

1. A pressure roller for a die cutting or coating machine, said roller comprising,

a cylinder having an axially extending slot in the outer periphery,

a resilient mat mounted on said cylinder,

and first magnetic means secured to said mat for insertion into said slot for magnetically holding the mat on the cylinder.

2. The roller according to claim 1 wherein said magnetic means comprises a channel member secured to the leading end of said mat and a strip of magnetic material positioned in said channel member for engagement with said cylinder.

3. The roller according to claim 1 wherein said magnetic means includes as econd magnetic means secured to the trailing end of the mat.

4. The roller according to claim 3 wherein said first and second magnetic means are secured to the leading and trailing ends for abutting engagement on insertion into the slot.

5. The roller according to claim 3 wherein said first and second magnetic means are secured to the leading and trailing ends of said mat for engagement with said cylinder on insertion into said slot.

6. The roller according to claim 1 including means positioned to engage said magnetic means for registering the mat on the cylinder.

7. The roller according to claim 3 wherein said first and second magnetic means each include a channel memher and a strip of permanent magnetic material extending across the full length of said member.

8. The roller according to claim 1 including a magnetic backing on the resilient mat for securing the mat to the roller.

9. A resilient mat for a pressure roller having an axially extending slot on the outer periphery, said mat comprising,

a single sheet of resilient material having a leading end and a trailing end and first magnetic means secured to said leading end for inserting into said slot.

10. The mat according to claim 9 wherein said magnetic means includes a channel shaped member and a permanent magnetic strip secured to said member.

11. The mat according to claim 9 including a second magnetic means secured to said trailing end for insertion into said slot.

12. The mat according to claim 11 wherein said first and second means are mounted for magnetic engagement with the roller.

13. The mat according to claim 11 wherein said first and second means are mounted for abutting magnetic engagement with each other.

References Cited UNITED STATES PATENTS 1,752,005 3/1930 Johnston 29-118 1,904,893 4/1933 Weidrich 29-130 UX 2,525,003 10/1950 Smith 29 11s UX 3,602,970 9/1971 Smith 29 11s 3,616,145 10/1971 Clifton 101-382 M v FOREIGN PATENTS 170,465 2/1960 Sweden -299 M ALFRED R. GUEST, Primary Examiner 

